It was estimated that 4,400 deaths would occur in the United States alone from this disease and 12,900 new cases of invasive cervical cancer would be diagnosed in 2001. Existing screening and detection techniques, the Pap smear and colposcopy, have several deficiencies that prevent efficient management of an otherwise controllable disease. An automated diagnostic with improved sensitivity and specificity that could allow for a "See and Treat" protocol would significantly improve the management of the disease. Optical spectroscopy can provide automated, fast and non-intrusive characterization of normal and non-normal tissues. In particular, Raman spectroscopy can be used to provide accurate differential diagnosis of early disease. Preliminary results indicate the potential of using Raman spectroscopy for the diagnosis of cervical precancers and to translate its application for the detection of vulvar disease. In particular, in vitro studies show that Raman spectroscopy can differentiate between cervical precancers and all other tissue categories with a sensitivity and specificity of 91 percent and 90 percent, significantly better than fluorescence spectroscopy. More importantly, the results from the initial 13 patients studied in vivo, indicate that 1 it is possible to measure Raman spectra from cervical tissue in vivo and (2) Raman spectroscopy can identify cervical lesions in vivo I (with spectra similar to that observed in vitro). Thus this proposal seeks to develop a real-time, optical method for the differential diagnosis of cervical precancerous lesions by providing real-time, automated, non-intrusive information of the tissue biochemistry and pathology. In addition, this proposal seeks to extend the capability of this technique to include vulvar disease. The specific aims of the proposed project are as follows; (1) Characterize Raman signatures of cervical tissues in vivo. (2) Develop diagnostic algorithms that separate normal and non- precancerous tissues from precancerous tissues. (3) Study the basis of observed differences in the spectral characteristics using microspectroscopy, cyto-chemical analysis, and modeling. (4) Conduct retrospective and prospective evaluation of the algorithms developed to obtain estimates of their performance. (5) Assess the feasibility of using optical spectroscopy for vulvar disease and verify the performance capability of this technique for vulvar precancer detection. (6) Develop software interface to implement and automate data acquisition and provide real-time diagnosis and to develop a compact clinical Raman system to reduce the scale of the system while maintaining its accuracy. These objectives when achieved will yield a method of obtaining real-time, non intrusive detection of cervical precancers that will facilitate the immediate management of the disease with high sensitivity and specificity. In addition, the potential of translating the application of Raman spectroscopy to other organs and in the vulva, in particular, will be assessed.